She stopped in and bought six large boxes of movie-theater candy and a king-size chocolate bar with one thought in mind. She planned to eat every last bite and then force herself to throw up.

Hodgins suffers from bulimia nervosa, an eating disorder that compels people to binge on large amounts of food and then purge the calories through vomiting, pills or excessive exercise.

Although most people think of eating disorders as a young person's problem, Hodgins is no teenager. She's a 53-year-old mother of two living in Philadelphia, and she's one of a disturbing number of middle-aged adults suffering from life-threatening eating disorders.

Midlife eating disorders

In June 2012 the prestigious International Journal of Eating Disorders published the results of a seminal study on the prevalence of eating disorders in midlife and beyond.

5 Signs You May Have an Eating Disorder

1. You make yourself vomit because you feel uncomfortably full.

2. You worry that you have lost control over how much you eat.

3. You've lost more than 14 pounds in a three-month period.

4. You believe yourself to be fat when others think you are too thin.

5. Thinking about food dominates your life.

Lead study author Cynthia Bulik, Ph.D., director of the Center of Excellence for Eating Disorders at the University of North Carolina, Chapel Hill, found that 13 percent of American women 50 or older experience symptoms of an eating disorder; 60 percent report that their concerns about weight and shape negatively affect their lives; and 70 percent are trying to lose weight.

Those figures mirror the rates found among teens and young women, says Bulik, author of Midlife Eating Disorders: Your Journey to Recovery.

"Eating disorders affect quality of life, and this has a tremendous impact on society," Bulik says. "It can affect productivity at work, well-being at home, and it can have very serious economic impacts" on families, as many insurance companies are reluctant to pay for care.

Although excessive concerns about weight can appear to be little more than vanity, an eating disorder is a mental illness with close links to depression and anxiety.

Besides bulimia, eating disorders include anorexia nervosa, which causes a person to starve herself even while underweight, and binge eating disorder, which causes a person to consume large amounts of food without purging.

Patients who meet some, but not all, of the criteria for anorexia or bulimia or have other symptoms (such as forcing themselves to vomit after eating normal amounts of food, or chewing and spitting out large amounts of food) may be diagnosed with other specified feeding and eating disorder (OSFED).

A mental health condition with a physical impact

Apart from the psychiatric impact of eating disorders — sufferers often isolate themselves from friends and family — these conditions also have a serious medical impact.

Anorexia is the deadliest of all psychiatric disorders, killing up to 20 percent of chronic sufferers. Starvation, binge eating and purging all damage the heart and gastrointestinal systems. Erratic eating can cause hormone imbalances that can lead to osteoporosis. Repeated vomiting and malnutrition damage teeth, too. These problems affect eating disorder sufferers of any age, but they hit harder and faster as people get older and their bodies become less resilient.

Although no one knows exactly what causes an eating disorder, researchers believe it results from a complex interaction between our genes and our environment. Eating disorders most commonly begin during adolescence, amid the swirling hormones, physical changes and psychological adjustments of puberty.

While some patients recover in their teens and 20s, others continue to struggle into midlife and beyond. Some of those who do recover will relapse later in life. And still others will develop an eating disorder for the first time in midlife.